1. Field of the Invention
This invention pertains to the field of treating waste products by combustion. It applies especially to the incineration of waste materials and mixtures of waste materials in all forms (solid, sludge, liquid) of all types (urban, industrial, hospital, etc.) and which can present environmental hazards (toxic, radioactive waste, etc.).
2. Description of the Prior Art
Waste incinerators, of which there are a variety of types such as static, rotating hearth, grid, fluid bed, plasma, etc., currently present a number of disadvantages. Among those disadvantages, the following can be cited:
- The lack of polyvalence, because the same type of incinerator generally can only treat certain types and forms of waste;
- Unsatisfactory fixation of incineration products, and primarily halogens, anhydrous gases, acids, nitrogen oxides, as well as heavy metals;
- Insufficient destruction of particularly stable products such as organochlorine compounds;
- Rapid deterioration of refractory walls due primarily to the presence of melted alkaline salts;
- Unsatisfactory hourly output taking into account the difficulties in heat evacuation;
- Frequent need to use a feed of oxygen-enriched air.
Of course, fluid bed-type incinerators ensure the correct destruction of certain types of waste, but said waste must be composed of fine particles, having a homogeneous granulometry, and the compound must only contain a small proportion of easily-fusible products, such as alkaline salts, in particular. Indeed, few waste materials meet these conditions, if only, for example, sludge from urban waste biological purification plants. However, in this case, the smoke from the incinerators contains toxic gases such as HCl, NOx, SO.sub.2, SO.sub.3, etc., which must then be treated with lime to produce yet another waste product.